drivers/mmc/host/renesas_sdhi_core.c | 6 ++++++ 1 file changed, 6 insertions(+)
For development purpose, renesas_sdhi_probe() could be called w/
dma_ops = NULL to force the usage of PIO mode. In this case the
renesas_sdhi_enable_dma() will not be called before transferring data.
If renesas_sdhi_enable_dma() is not called, renesas_sdhi_clk_enable()
call from renesas_sdhi_probe() will configure SDBUF by calling the
renesas_sdhi_sdbuf_width() function, but then SDBUF will be reset in
tmio_mmc_host_probe() when calling tmio_mmc_reset() though host->reset().
If SDBUF is zero the data transfer will not work in PIO mode for RZ/G3S.
To fix this call again the renesas_sdhi_sdbuf_width(host, 16) in
renesas_sdhi_reset(). The call of renesas_sdhi_sdbuf_width() was not
removed from renesas_sdhi_clk_enable() as the host->reset() is optional.
Co-developed-by: Hien Huynh <hien.huynh.px@renesas.com>
Signed-off-by: Hien Huynh <hien.huynh.px@renesas.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---
Changes in v2:
- fixed typos in commit description
- limit the comment lines to 80 chars
drivers/mmc/host/renesas_sdhi_core.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c
index f84f60139bcf..5233731a94c4 100644
--- a/drivers/mmc/host/renesas_sdhi_core.c
+++ b/drivers/mmc/host/renesas_sdhi_core.c
@@ -589,6 +589,12 @@ static void renesas_sdhi_reset(struct tmio_mmc_host *host, bool preserve)
sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
priv->needs_adjust_hs400 = false;
renesas_sdhi_set_clock(host, host->clk_cache);
+
+ /*
+ * In case the controller works in PIO mode the SDBUF
+ * needs to be set as its reset value is zero.
+ */
+ renesas_sdhi_sdbuf_width(host, 16);
} else if (priv->scc_ctl) {
renesas_sdhi_scc_reset(host, priv);
}
--
2.39.2Hi Claudiu, On Wed, Apr 10, 2024 at 04:54:16PM +0300, Claudiu Beznea wrote: > For development purpose, renesas_sdhi_probe() could be called w/ > dma_ops = NULL to force the usage of PIO mode. In this case the > renesas_sdhi_enable_dma() will not be called before transferring data. > > If renesas_sdhi_enable_dma() is not called, renesas_sdhi_clk_enable() > call from renesas_sdhi_probe() will configure SDBUF by calling the > renesas_sdhi_sdbuf_width() function, but then SDBUF will be reset in > tmio_mmc_host_probe() when calling tmio_mmc_reset() though host->reset(). > If SDBUF is zero the data transfer will not work in PIO mode for RZ/G3S. > > To fix this call again the renesas_sdhi_sdbuf_width(host, 16) in > renesas_sdhi_reset(). The call of renesas_sdhi_sdbuf_width() was not > removed from renesas_sdhi_clk_enable() as the host->reset() is optional. So, I tried to find a place where we would need only one call to renesas_sdhi_sdbuf_width() but I also couldn't find a sweet spot. So, this approach seems also best to me. > + > + /* > + * In case the controller works in PIO mode the SDBUF > + * needs to be set as its reset value is zero. > + */ But I think we can shorten the above comment to something like: /* Ensure default value for this driver */ > + renesas_sdhi_sdbuf_width(host, 16); D'accord? Happy hacking, Wolfram
Hi, Wolfram, On 30.04.2024 12:10, Wolfram Sang wrote: > Hi Claudiu, > > On Wed, Apr 10, 2024 at 04:54:16PM +0300, Claudiu Beznea wrote: >> For development purpose, renesas_sdhi_probe() could be called w/ >> dma_ops = NULL to force the usage of PIO mode. In this case the >> renesas_sdhi_enable_dma() will not be called before transferring data. >> >> If renesas_sdhi_enable_dma() is not called, renesas_sdhi_clk_enable() >> call from renesas_sdhi_probe() will configure SDBUF by calling the >> renesas_sdhi_sdbuf_width() function, but then SDBUF will be reset in >> tmio_mmc_host_probe() when calling tmio_mmc_reset() though host->reset(). >> If SDBUF is zero the data transfer will not work in PIO mode for RZ/G3S. >> >> To fix this call again the renesas_sdhi_sdbuf_width(host, 16) in >> renesas_sdhi_reset(). The call of renesas_sdhi_sdbuf_width() was not >> removed from renesas_sdhi_clk_enable() as the host->reset() is optional. > > So, I tried to find a place where we would need only one call to > renesas_sdhi_sdbuf_width() but I also couldn't find a sweet spot. So, > this approach seems also best to me. > >> + >> + /* >> + * In case the controller works in PIO mode the SDBUF >> + * needs to be set as its reset value is zero. >> + */ > > But I think we can shorten the above comment to something like: > > /* Ensure default value for this driver */ >> + renesas_sdhi_sdbuf_width(host, 16); > > D'accord? Ok! I'm going to prepare a new version to change the comment. Thank you, Claudiu Beznea > > Happy hacking, > > Wolfram >
On Wed, 10 Apr 2024 at 15:54, Claudiu Beznea <claudiu.beznea@tuxon.dev> wrote:
>
> For development purpose, renesas_sdhi_probe() could be called w/
> dma_ops = NULL to force the usage of PIO mode. In this case the
> renesas_sdhi_enable_dma() will not be called before transferring data.
>
> If renesas_sdhi_enable_dma() is not called, renesas_sdhi_clk_enable()
> call from renesas_sdhi_probe() will configure SDBUF by calling the
> renesas_sdhi_sdbuf_width() function, but then SDBUF will be reset in
> tmio_mmc_host_probe() when calling tmio_mmc_reset() though host->reset().
> If SDBUF is zero the data transfer will not work in PIO mode for RZ/G3S.
>
> To fix this call again the renesas_sdhi_sdbuf_width(host, 16) in
> renesas_sdhi_reset(). The call of renesas_sdhi_sdbuf_width() was not
> removed from renesas_sdhi_clk_enable() as the host->reset() is optional.
>
> Co-developed-by: Hien Huynh <hien.huynh.px@renesas.com>
> Signed-off-by: Hien Huynh <hien.huynh.px@renesas.com>
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Wolfram, when you have the time, can we get your opinion on this one?
Kind regards
Uffe
> ---
>
> Changes in v2:
> - fixed typos in commit description
> - limit the comment lines to 80 chars
>
> drivers/mmc/host/renesas_sdhi_core.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c
> index f84f60139bcf..5233731a94c4 100644
> --- a/drivers/mmc/host/renesas_sdhi_core.c
> +++ b/drivers/mmc/host/renesas_sdhi_core.c
> @@ -589,6 +589,12 @@ static void renesas_sdhi_reset(struct tmio_mmc_host *host, bool preserve)
> sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
> priv->needs_adjust_hs400 = false;
> renesas_sdhi_set_clock(host, host->clk_cache);
> +
> + /*
> + * In case the controller works in PIO mode the SDBUF
> + * needs to be set as its reset value is zero.
> + */
> + renesas_sdhi_sdbuf_width(host, 16);
> } else if (priv->scc_ctl) {
> renesas_sdhi_scc_reset(host, priv);
> }
> --
> 2.39.2
>
On Fri, Apr 26, 2024 at 07:08:10AM +0200, Ulf Hansson wrote: > On Wed, 10 Apr 2024 at 15:54, Claudiu Beznea <claudiu.beznea@tuxon.dev> wrote: > > > > For development purpose, renesas_sdhi_probe() could be called w/ > > dma_ops = NULL to force the usage of PIO mode. In this case the > > renesas_sdhi_enable_dma() will not be called before transferring data. > > > > If renesas_sdhi_enable_dma() is not called, renesas_sdhi_clk_enable() > > call from renesas_sdhi_probe() will configure SDBUF by calling the > > renesas_sdhi_sdbuf_width() function, but then SDBUF will be reset in > > tmio_mmc_host_probe() when calling tmio_mmc_reset() though host->reset(). > > If SDBUF is zero the data transfer will not work in PIO mode for RZ/G3S. > > > > To fix this call again the renesas_sdhi_sdbuf_width(host, 16) in > > renesas_sdhi_reset(). The call of renesas_sdhi_sdbuf_width() was not > > removed from renesas_sdhi_clk_enable() as the host->reset() is optional. > > > > Co-developed-by: Hien Huynh <hien.huynh.px@renesas.com> > > Signed-off-by: Hien Huynh <hien.huynh.px@renesas.com> > > Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> > > Wolfram, when you have the time, can we get your opinion on this one? Sure, I'll try to squeeze it in today. Thanks for the heads up!
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